The invention relates to a conductor rail having a rail-like support section made of metallic material, in particular a support section which is I-shaped in cross-section and has at least one component of another metal attached to it. Furthermore, the scope of the invention includes a use of the conductor rail and a process for its manufacture.
Known from U.S. Pat. No. 5,918,712 is a composite section featuring a support section or body made of light weight metallic material and at least one strip of another material of greater wear resistance which is joined to the support section or body during extrusion. Composite sections that are I-shaped in cross-section and exhibit a rail base, rail neck and rail head are described, the head part being covered by a strip running in the direction of the longitudinal axis; the latter provides a wear-resistant power transfer surface for the sliding contact shoe. This composite section is manufactured out of an aluminium alloy by means of extrusion in one single step during which the strip is fed into the extrusion press.
Known from U.S. Pat. No. 4,215,560 is a process for manufacturing conductor rails from a support section and at least one strip of another metal which forms at least part of the covering surface of the support section. Also here the support section is formed during extrusion by pressing a block of metal through the shape-giving opening of an extrusion die; at the same time the strip runs through the die opening parallel to the longitudinal axis of the die. Also--on making use of strips that have not been plated in advance--at least two composite sections are produced simultaneously, this in order to ensure adequate bonding between the support section and the covering layer; the areas of support section to be provided with a covering layer face each other and are fed a pair of strips that are in contact with each other and pass through the shape-giving opening in the die.
Although new power supply units are fitted with aluminium/steel composite conductor rails--this in view of their significantly better electrical conductivity--the electrification of the larger part of the approximately 11'000 km stretch of railway line, in particular in underground railways, involves soft iron conductor rails and so called light mail vehicles.
Retro-fitting such oonductor systems involves exchanging the conductor rails completely, which means down time and therefore--in addition to the investment and installation costs--also considerable losses due to down time on the stretch of track in question.
In view of this state of the art the object of the present invention is to enable steel conductor rails to be retrofitted; it should be possible to retro-fit the whole power supply facility with a ready-made conductor rail that meets the requirements e.g. during overnight down time and without expensive installation costs. Furthermore, it should be possible to employ ready assembled conductor rails with profile rails for new installations.